The rule

If it did not grow, it does not ship.

A thick sweatshirt is a simple object. Cloth, rib, thread, maybe a zipper. The market has made it complicated by stirring polyester into the fleece "for durability," elastane into the cuff "for recovery," and nylon into merino "so it lasts." The hand goes slick. The thing pills into plastic dots. It stops feeling like a sweatshirt.

This site lists a garment only when the seller's own page describes every stated component as a natural fiber: cotton, wool, merino, linen, hemp, cashmere, alpaca, silk, and the rest of that family. One synthetic part is enough to keep it out. That includes ribbing, a lining, and a fill. A hoodie that is cotton in the body and spandex in the cuff is a blend. We do not average it into a yes.

What thickness is doing

Weight is warmth, wind resistance, and how the garment hangs after a year. A modern "heavyweight" is often 8 or 9 ounces and full of recovery yarns. A 14 ounce cotton fleece or a 20 ounce loopwheel does the job by being cloth. Wool does it with crimp and air, which is why a merino hoodie can be serious without approaching the grams of a Wonder Looper. We say which kind of thick each listing is, and we leave the number blank when the seller did.

What we are not claiming

• Natural is not a moral award. Cotton has a water and labor history. Wool has a land history. The fiber rule is about what the shirt is, not a halo.
• Organic is recorded when the seller says it. It is not assumed from a nice adjective.
• A thin 100% cotton tee is natural and none of our business. So is a 170 GSM merino sun hoodie. This is a thick list.
• Regenerated cellulose — rayon, viscose, modal, lyocell — is rejected. It started as a plant and went through a solvent bath.

The ribbing trick

Read the materials line twice. Plenty of good makers will say "100% cotton" in the first sentence and "ribs: 95% cotton, 5% elastane" in the second. American Giant's wholesale spec does this. Sunspel does this. Dehen's Heavy Duty sweat does this, at 19 ounces, which hurts. The consumer page sometimes drops the second sentence. We keep the second sentence.

When a seller gives one composition for the whole garment and it is entirely natural, the piece can be listed. The card says whether the rib was itemized. Silence is not the same as a disclosed blend, and it is also not a lab test. We are reading the page, not burning the shirt.

Care, briefly

Cotton fleece without elastane can shrink and can grow. Wash cold, skip the hot dryer if you like the fit you bought. Wool and merino felt if you shock them with heat and agitation; lay them flat. Hemp softens. None of these fibers need a plastic content to be worth wearing. They need weight, and a maker willing to print the truth.